折线图的背景是否支持Y轴0以上一个背景色，0以下一个背景色，Help me！

[hanyongchao]

🐛 Question description [Please make everyone to understand it]

💻 Link to minimal reproduction

Please provide a link by forking these links g2plot or GitHub repo. What is a minimal reproduction, and why is it required?

🏞 Expected result

🚑 Any additional [like screenshots]

• G2Plot Version:
• Platform:

[TopAlien]